Engineering the crystal facets of Pt/In2O3 catalysts for high-efficiency methanol synthesis from CO2 hydrogenation

Hydrogenation of CO 2 to methanol is an achievable way for “methanol economy” and “liquid sunshine” visions. Owing to highly tunable properties containing different morphologies, exposed crystal facets and oxygen vacancies , In 2 O 3 has become a promising material for CO 2 hydrogenation. Here we successfully introduced highly dispersed Pt 2+ species into three different morphologies In 2 O 3 supports by controllable precipitation method. The dominant exposed crystal facets of In 2 O 3 supports during the research are discovered to greatly affect the dispersion of active Pt 2+ species and the number of oxygen vacancies, as analyzed by diverse characterization techniques, and closely correlated with the catalytic performance. Compared with Pt/In 2 O 3 whcih mainly exposing (222) or (104) facet, Pt/In 2 O 3 which primarily exposed (211) facet obtained higher catalytic activity, including a CO 2 conversion of 11.7% and methanol selectivity of 74.8% with a space time yield of methanol of 0.63 g MeOH h −1 gcat −1 at 300 °C, 5 MPa, and 21,000 cm 3 h −1 g −1 . The highly enhanced activity of 1.5Pt/C-In 2 O 3 -S catalyst was ascribed to its more abundant oxygen vacancies and well-dispersed Pt 2+ species, which derived from the interaction between Pt 2+ and the underlying In 2 O 3 (211) facet. The special interface structure enabled the activation of CO 2 and hydrogenation of key intermediates effectively. Exposing the highly active crystal face of the In 2 O 3 supports is proved to be an effective strategy to enhance catalytic performance of Pt/In 2 O 3 catalyst for methanol synthesis .